66 W. A. Norton on Molecular Physics. 
| 
distinguished from other electric currents, has just been indicated. 
The existence of such currents in the surface of a compound 
molecule seems to imply that there is a virtual chain of particles 
extending circularly around it, which there would be if the num- 
ber .of particles in each group be large. Ampére’s researches 
have completely established that the idea‘of ciréular molecular 
currents is the key to all magnetic phenomena. It suffices, there- 
fore, for our present purpose, to show, as has been done, that 
such currents are legitimately deducible from the fundamental 
conceptions laid down at the outset; and that the mutually attrac- 
tive and repulsive actions of currents may also be derived from 
= Mba 
effect upon the particles in the surface of compound molecules. 
In respect to magnetic properties, we have specially to distin- 
guish soft iron and steel. The cause of their difference of prop- _ 
erty seems to lie simply in a difference in the conducting power | 
of the groups of particles into which they are ageregated. : 
in soft iron these groups are good conductors, the electric ether 
set in motion should pass freely around them, unattended with 
any material polarization of the particles, and unresisted by the 
force that results from such polarization, (p. 245). When the 
exciting cause ceases to operate, there is no force remaining to 
counteract the resistance of the universal ether to the flow of 
the electricity, and the retarding operation of contiguous oppos- : 
ing currents. But if we suppose that, in the case of steel, the 
2 It is worthy of consideration, whether certain phenomena of luminosity, a3 
ce, heat , may not have a similar origin, viz: in r 
ring discharges resulting from a previous molecular polarization, established by 20 
electric discharge through the mass; or from a dicatlar effect produced in a feebler 
degree by heat or light. 
a 
